S6 Wagon L5-2226cc 2.22L DOHC Turbo (AAN) (1995)
Internal resistance check.
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Disconnect MAF sensor harness connector.
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Switch DVOM to 200 ohm range.
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Connect multimeter (using VW 1594 connector test kit) to MAF sensor terminals 1 and 2.
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Record resistance value.
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Disconnect test leads from MAF sensor, and connect test leads together.
^
Display value must equal value recorded previously.
If difference is greater than 0.1 ohm:
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Replace MAF sensor.
Output signal check.
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Re-connect MAF sensor harness connector.
Mass Air Flow Sensor Connection
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Peel back rubber boot on back of harness connector to expose terminals.
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Switch multimeter to 20 Volt range.
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Connect multimeter to (exposed) terminals 1 and 3.
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Switch ignition ON.
^
Must be 1.2 - 1.5 Volts.
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Start engine and let idle.
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Must be approx. 2.5 Volts.
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Increase Engine Speed (RPM) briefly.
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Voltage must increase to 3.0 - 5.0 Volts
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All of the specified voltages must be obtained.
If not:
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Replace MAF sensor.
Checking MAF sensor burn-off
Note: The sensing element of the MAF sensor must be clean to function properly. To accomplish this, the element is heated to 100°C (183°F) for
one second, each time the ignition is switched OFF.
Burn-off occurs only under the following conditions:
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Engine Coolant Temperature (ECT) above 60°C (140°F).
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Engine Speed (RPM) has exceeded 2000 rpm for at least 3 seconds.
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MAF sensor wiring is OK.
^
Injector valve circuit breaker S72 is OK.
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Disconnect MAF sensor from air cleaner housing and position far enough back so that burn-off process can be observed.
Note: Do not disconnect the intake air hose or the MAF sensor connector.
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Start engine and let idle above 2000 RPM for minimum of 3 seconds.
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Switch ignition OFF.
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Observe burn-off process.
^ Heating wire glows for about 1 second.
If NO:
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Position aside rubber sleeve on MAF sensor connector.
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Connector must remain connected to MAF sensor Connect US 1115 LED tester or equivalent to terminals 1 and 4.